Flat bed trailers have been used increasingly to transport timber, lumber, metal stock, machinery and other cargo. The cargo is usually secured to the flat bed using long flexible straps carried on winches mounted to the underside of the flat bed. In a typical cargo securing operation, a suitable length of strap is drawn from the winch, placed across the top of the cargo and attached to both sides of the flat bed.
Once the cargo is removed from the flat bed, it becomes necessary to rewind the length of strap onto the winch for safe storage. This task is often performed by manually rotating the hub member which projects from the side of the winch bracket. More specifically, the operator or user grasps the hub member and turns the hub member manually in angular increments in the winch take-up direction to effect winding of the strap onto the winch. When performed in this manner, the winding tends to be carried out in an discontinuous or interrupted fashion because the user is required to constantly readjust his grip on the hub member. The user's efforts may be further hampered by the little clearance which may exist between the hub member and the flat bed. As a result, manual winding tends to be a highly inefficient, tedious, time-consuming and labour-intensive procedure. Furthermore, because of the repetitive nature of the movement, the user may be at risk of developing repetitive strain disorder or other such condition. These problems are further compounded or exacerbated in the case where this procedure needs to be repeated to effect strap winding on multiple winches.
Several attempts have been made to facilitate the winding of a strap onto a winch. One such example is described in U.S. Pat. No. 5,791,844 issued to Anderson. This patent relates to a portable crank assembly provided with a handle, an expandable compression member adapted for insertion into the hollow core of the hub member and a bar connecting the handle to the compression member. The compression member is attached to the bar with a bolt and wing nut. The bolt extends through the compression member and carries thereon a backup washer which bears against the compression member. By tightening the wing nut on the bolt, the backup washer can be drawn against the compression member to thereby apply a compressive force on the compression member. The application of this force causes the compression member to expand outwardly for frictional engagement with the inner wall of the winch hub member. Thus arranged, the crank assembly and hub member can be locked together for rotation. To wind the strap onto the winch, the user grasps the grip element of the handle and manually operates the crank assembly. The crank assembly can be decoupled from the hub member by loosening the wing nut to allow the compression member to return to its original shape and size and be disengaged from the hub member.
While this crank assembly tends to constitute an improvement over manual winding of the strap onto the winch, there are concerns that the device is not sufficiently robust to resist wear arising from repeated use. In particular, the compression member of the crank assembly may be prone to excessive wear and accordingly, may require frequent replacement. In addition, because of its configuration, the repeated use of this device may still present some risk of injury to the user by placing undue strain on the wrist of the user.
Another approach to winding a strap onto a winch was taken in U.S. Pat. No. 6,102,637 issued to Mocci. This patent describes a winch winding bar in the nature of a steel rod in which several bends have been formed therein to define two rod portions which are axially offset from each other. Sleeves are fitted over these rod portions and provide a surface which may be gripped by the user when using the winch winding bar. A hook is formed at one end of the steel rod for receipt within the apertures defined in the annular wall of the hub member. The hook provides an interface to the winch and serves to transfer the rotary motion from the winding bar to the winch. To wind the strap about the winch, the user inserts the hook into the apertures of the hub member, places his/her hands on the sleeves and then applies a rotary force on the winch winding bar. As the winding bar rotates, the strap becomes wound onto the winch. While this device obviates the drawbacks associated with the portable crank assembly described above, its operation requires the use of two hands which may not be desirable in certain field applications.
In light of the foregoing, it would be advantageous to have a portable apparatus for mechanically winding a strap onto the winch that is of robust construction, is safe, simple and quick to use and does not require two hands during operation.